Means for establishing electric circuits.



.No. 788,563. PATENTED MAY 2, 1905.

G. THOMPSON. I MEANS FOR ESTABLISHING ELECTRIC CIRCUITS.

APPLICATION FILED JULY 1, 1902.

W127 85S 63: lfivep dz- QAZ 5010 71117411 50 119s (filing:

UNITED STATES Patented May 2, 1905.

' PATENT OFFICE.

GUION THOMPSON, OF DULUTH, MINNESOTA, ASSIGNOR TO THE THOMP- SON SAFETYAPPLIANCE COMPANY, A CORPORATION OF NEW JERSEY.

MEANS FOR ESTABLISHING ELECTRIC CIRCUITS.

SPECIFICATION forming part of Letters Patent No. 788,563, dated MayApplication filed July 1, 1902. Serial No. 113.9 16.

To all whom it may concern/.-

Be it known that I, GUIoN THOMPSON, a citizen of the United States,residing at Duluth, in the county of St. Louis and State of Minnesota,have invented new and useful Means for Establishing Electric Circuits,of which the followin is a specification.

My invention re ates to means for establishing an electric circuit, andhas for its obj ect the provision of means whereby such circuit may beestablished from a battery or other source of electricity carried by amoving conveyance through stationary conductors of electricity locatedupon the route of said conveyance.

It comprises the combination of a source of electricity carried by amovable conveyance, electricity-conducting means connected to one of thepoles of said source and adapted to contact with stationaryelectricity-conducting means located upon the route of said conveyance,electricity-conducting means connected to the other pole of said sourceand adapted to contact with a second stationary conductor of electricitylocated upon said route, a series of intermediate conductors ofelectricity located upon said route and eX- tending from one of saidstationary conductors to the other and forming a normally operativeconductor from said first to said second stationary conductor adapted tobe interrupted by the movement of the support of one of the elements ofsaid series.

It also consists of certain other constructions, combinations, andarrangement of parts, as will be hereinafter described.

In the drawings, Figure 1 is a diagram of the portions of said circuitwhich are anchored upon the route of said conveyance. Fig. 2 is adiagram of a movable conveyance upon said route and of the portions ofsaid circuit carried thereby, showing in dotted lines a lamp-circuitwhich my invention may be made to interrupt. Fig. 3 is a detail of amodified construction of a part of said anchored portions.

In the drawings, A and A, respectively, represent the rails of arailway-track, and A is a short rail or contact external to the rails ofsaid track and preferably supported by a support (1. Connected at oneend to said external rail A and extending backward a suitable distancealong said track is a conductor of electricity A, provided at itsopposite end with a contact e. Connected at one end to said rail A andextending therefrom to the vicinity of said contact 6 is a conductor ofelectricity A provided with a terminal contact e, adapted toelectrically communicate with said contact a through the medium of adouble intervening or bridging contact e as shown in Fig. 1, or by anyother suitable means, which contactual or communicating relation isadapted to be controlled by a positiongoverning means of any suitableconstruction, as an armature A of an electromagnet A anchored in anysuitable manner on the bed of said track, to which armature said doublecontact e is attached and by which it is adapted to be temporarilywithdrawn from contact with said contacts 6 and e when said armature isattracted toward said electromagnet or otherwise moved from its normalposition. It is obvious, however, that said contact e may within thescope of my invention be made to normally contact directly with saidcontact 6, as shown in Fig. 3, under the control of suchposition-governing means by attaching either of said. contacts c or c tosaid means A" in a position to contact with the other and relativelydetached one of said contacts, or any other suitable construction may beemployed which will efiect equivalent relations between said conductorsA and A". The coil of said electromagnet A is-included in a normallyopen circuit comprising a battery A or other source of electricity, theconductor A", the normally closed circuit-breaker A, the con ductor A,the conductor A", the front stop A and the normally open circuit-closeror armature A. B represents a locomotive or other conveyance adapted tomove on said rails A and A, which conveyance carries a battery 6 orother source of electricity, to the opposite poles of which areconnected conductors of electricity, as at I) and b, of any suitablematerial or construction and normally so separated or insulated fromeach other as to be electrically nonintercommuni cative,-the conductor bbeing adapted to contact, through the medium of the axle and wheel ofthe conveyance, forming a conductual extension thereof, with the rail A,the

conductor 5 being adapted to contact directly or through a suitableterminal contact, as 5*, with said external rail A Said conveyance alsocarries a magnet or energized electromagnet H, which is adapted in passing said armature A to attract and operate the same, either directly orthrough the medium of said electromagnet A and is further adapted whenpassing said circuit-breaker A to operate the same to open the circuitcontrolled thereby. Said battery I) may also be included in a normallyclosed circuit including portions of said conductors b and b and asignal-lamp C. (Shown in dotted lines on said conveyance.) It is obviousalso that said conductor A may, within the scope of my invention, beattached to either one of said rails A or A, or, if desired, to a secondexternal rail or contact similar to said rail A placed transversely ordiagonally opposite to said rail A preferably forward of said armatureA, in which latter event the conductor b may be constructed in a mannersimilar to conductor 6 and arranged to contact with such second externalrail at the same time that said conductor 6 contacts with said rail A Itis regarded as one of the essential features of my invention that theconstruction thereof shall be such that said means A may normally beoperated by some operating means on the conveyance, directly or throughintermediate means, to interrupt the electroconductual relation betweensaid contacts a and e shortly before the conductors o and b have bothcontacted with their corresponding rail-contacts, which requirement iscomplied with, preferably, by leading said conductor A backward fromsaid external rail A and by placing said rail A forward of saidgoverning means A", as shown but I do not desire to limit myself to suchexact construction, since the same re sults may be attained by modifiedor extended constructions within the spirit and scope of my saidinvention.

The operation of my said invention is as follows: When a conveyance soequipped passes from left to right along said route, the road-bedequipment and the conveyance equipment being in working order, themagnet H directly or through the medium of the magnet A will firstoperate the armature A to close the circuit including said battery A, bywhich the energy of said magnet A will be maintained. The movement ofsaid armature will suspend the conductive communication between theconductors A and A When, therefore, the conductors b and b aresubsequently brought into contemporaneous contact, respectively, withconductors A and A, no current passes from said battery I) through saidconductors A and A, and said lamp Cremains lighted. If,how ever, saidcircuit including said battery A fails of operation, said armature Awill be dropped as soon as passed by said magnet H and the conductivecommunication reestablished from conductor A to conductor A in whichevent when the conveyance brings said conductors b and 6 simultaneouslyinto contact with said conductors A and A, respectively, the currentfrom battery I) will be short-circuited from said lamp C, and theconsequent extinction of the light thereof will give warning that thecircuit including said battery A failed, which operation is regarded asof very great importance and may be characterized as a "fail-to-dangerconstruction as distinguished from a construction by which the failureof the assumed circuits will leave a safety-signal displayed in the cabof the en ine.

The ut' ities of my invention are manifold, and one of them may besuggested by the fact that said magnet A when energized and continued inoperation by the means described is adapted to operate additional means(not shown) carried by a following conveyance to warn the driver of suchfollowing conveyance of the presence of the preceding conveyance betweenthe positions of the magnet A and the circuit-breaker A The failure ofthe circuit in which said magnet A is included would incapacitate saidmagnet for such service, and but for the failto-danger constructionherein described the driver of said following conveyance, ignorant ofthe failure of the signal system, might continue to a collision with thepreceding conveyance. It is obvious that my said invention may bemodified or extended in minor details and that such contacts andconductors may be constructed in any suitable manner or of any suitablematerials or supported by any suitable means or in any suitable mannerand that any suitable source of electricity of any suitable constructionmay be substituted for said battery I), all within the scope of my saidinvention.

Having now described my said invention, what I claim, and desire tosecure by Letters Patent, is-

1. The combination of a normally open electric circuit including asource of electricity, electromagnetic means and a normally open circuitcontrolling contact; a partial circuit including a normally closedcontact and a normally open contact; means governed by saidelectromagnetic means and adapted when operated thereby to close ormaintain the closure of the first said normally open circuit-controllingcontact; means governed by said electromagnetic means and adapted whenoperated thereby to open said ITC normally closed contact; a travelinbridging contact constituting a normally open electric circuit andincluding a source of electricity and adapted during passage to closefor a brief period the normally open contact of said partial circuit,and an electrically-operated device governed by said normally opentraveling circuit.

2. The combination of a normally open electric circuit including asource of electricity the coil of an electromagnet and a normally opencircuit-controlling contact; a partial circuit, including a normallyclosed circuit-controlling contact and a normally opencircuit-controlling contact; an armature for said electromagnet adaptedWhen operated thereby to close the first said normally open contact atraveling bridging contact, constituting a normally open electriccircuit and including a source of electricity and adapted during assageto close for a brief period the norma y open contact of said partialcircuit; a closed electric circuit of relatively high resistanceincluding the last said source of electricity and a part of the saidnormally open traveling circuit, or traveling contact, and anelectrically-operated signal device.

In testimony whereof I have signed this specification in the presence oftwo subscribing Witnesses.

GUION THOMPSON.

